openwrt/target/linux/generic/pending-4.19/203-kallsyms_uncompressed.patch
Hauke Mehrtens 52a82ce3dd kernel: Copy patches from kernel 4.14 to 4.19
This just copies the files from the kernel 4.14 specific folders into
the kernel 4.19 specific folder, no changes are done to the files in
this commit.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2018-12-15 12:50:06 +01:00

120 lines
3.4 KiB
Diff

From: Felix Fietkau <nbd@nbd.name>
Subject: kernel: add a config option for keeping the kallsyms table uncompressed, saving ~9kb kernel size after lzma on ar71xx
[john@phrozen.org: added to my upstream queue 30.12.2016]
lede-commit: e0e3509b5ce2ccf93d4d67ea907613f5f7ec2eed
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
init/Kconfig | 11 +++++++++++
kernel/kallsyms.c | 8 ++++++++
scripts/kallsyms.c | 12 ++++++++++++
scripts/link-vmlinux.sh | 4 ++++
4 files changed, 35 insertions(+)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1081,6 +1081,17 @@ config SYSCTL_ARCH_UNALIGN_ALLOW
the unaligned access emulation.
see arch/parisc/kernel/unaligned.c for reference
+config KALLSYMS_UNCOMPRESSED
+ bool "Keep kallsyms uncompressed"
+ depends on KALLSYMS
+ help
+ Normally kallsyms contains compressed symbols (using a token table),
+ reducing the uncompressed kernel image size. Keeping the symbol table
+ uncompressed significantly improves the size of this part in compressed
+ kernel images.
+
+ Say N unless you need compressed kernel images to be small.
+
config HAVE_PCSPKR_PLATFORM
bool
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -108,6 +108,11 @@ static unsigned int kallsyms_expand_symb
* For every byte on the compressed symbol data, copy the table
* entry for that byte.
*/
+#ifdef CONFIG_KALLSYMS_UNCOMPRESSED
+ memcpy(result, data + 1, len - 1);
+ result += len - 1;
+ len = 0;
+#endif
while (len) {
tptr = &kallsyms_token_table[kallsyms_token_index[*data]];
data++;
@@ -140,6 +145,9 @@ tail:
*/
static char kallsyms_get_symbol_type(unsigned int off)
{
+#ifdef CONFIG_KALLSYMS_UNCOMPRESSED
+ return kallsyms_names[off + 1];
+#endif
/*
* Get just the first code, look it up in the token table,
* and return the first char from this token.
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -61,6 +61,7 @@ static struct addr_range percpu_range =
static struct sym_entry *table;
static unsigned int table_size, table_cnt;
static int all_symbols = 0;
+static int uncompressed = 0;
static int absolute_percpu = 0;
static char symbol_prefix_char = '\0';
static int base_relative = 0;
@@ -457,6 +458,9 @@ static void write_src(void)
free(markers);
+ if (uncompressed)
+ return;
+
output_label("kallsyms_token_table");
off = 0;
for (i = 0; i < 256; i++) {
@@ -515,6 +519,9 @@ static void *find_token(unsigned char *s
{
int i;
+ if (uncompressed)
+ return NULL;
+
for (i = 0; i < len - 1; i++) {
if (str[i] == token[0] && str[i+1] == token[1])
return &str[i];
@@ -587,6 +594,9 @@ static void optimize_result(void)
{
int i, best;
+ if (uncompressed)
+ return;
+
/* using the '\0' symbol last allows compress_symbols to use standard
* fast string functions */
for (i = 255; i >= 0; i--) {
@@ -775,6 +785,8 @@ int main(int argc, char **argv)
symbol_prefix_char = *p;
} else if (strcmp(argv[i], "--base-relative") == 0)
base_relative = 1;
+ else if (strcmp(argv[i], "--uncompressed") == 0)
+ uncompressed = 1;
else
usage();
}
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -164,6 +164,10 @@ kallsyms()
kallsymopt="${kallsymopt} --base-relative"
fi
+ if [ -n "${CONFIG_KALLSYMS_UNCOMPRESSED}" ]; then
+ kallsymopt="${kallsymopt} --uncompressed"
+ fi
+
local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \
${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}"